Dry spray equipment



DRY SPRAY EQUIPMENT Filed April 30. 1948, 4 Sheets-Sheet 1 I JO w ATTO RN EYS Oct. 21, 1952 c. w. BRN-CHER DRY SPRAY EQUIPMENT 4 Sheets-Sheet 2Fi led April 50. 1948 lNvENToR @Aanleg m'zzzamfchef ATTORNEYS Oct. 21,1952 c. w. BRITCHER DRY SPRAY EQUIPMENT 4 Sheets-Sheet 3 Fi led April30, 1948 Slg/M' '.Oct. 2l, 41952 Q W, BRN-CHER 2,614,528

DRYv SPRAY EQUIPMENT n Filed April 30. 1948 4 Sheets-Sheet 4 ATTORN YSPatented Qct. 21, .1952

@misma y what requires :mi f gl nmel wish- .a mltiple outlet fitting,

Y' as-kefo 11216 "between me munication to the interior of thedehydrator tank The bottom of the dehydrator ,.tank is' also providedwith a pet cock 43, the mounting nipple 44 of which is threaded into ahollow plug 45 may be viewable through sight glass 8 I', the upperthreaded into an opening in the bottom of th'e" dehydrator tank 35.

held in place as by soldering.

The deny/crater tank so uesirabiy is cned with f f a drying compositionsuch as silica gel of the tell- The bore of plug 45vhas ag; seat 4t onwhich is positioned a screendisc 41,

tale type and is also desiralolyl provided witha sight glass 43comprising a bushing 49 threaded into an opening in the wall of thedehydrator tank A 3G and having a glass disc 5| ainxed by cementing orgluing on a seat 52 at the inner end ofthe bushing. Y

A bushing 33 threaded vinto an opening at the top of tank 3|). has atapped bore 54 reduced to form a seat 55 on vvhich'a mesh screen disc 56is placed. The screen is retained on Vits seat by a lock sleeve 51threaded into :bore 54 and which has lateral openings 58 aordingcommunication with theinterior of the dehydrator tank 3J.V Y

From the top of tank 30 a pipe159 threaded into bushing 53, leads intosolenoidvalve 6| which as it is conventional in constructionwill. notvbe described in detail. n l Y,

Valve di which whendeenergized is in closed posi-tion, is connected bycross conduit 62 and pipe t3 to pressure regulator .E4 the latter havinga pressure gauge 65 associated therewith. From regulator E4, pipe 65leads to `needle valve 61 which has a nipple 38 threaded into the lowerend of the bore 69 of air inlet plug 1|. The latter is threaded into anopening at the bottom of spray tank 24 which also has a drain plug 12therein,

In order to form a cloudofpowder in'the'tank, stationary means areprovided to directa 'stream or jet of air into the powder in such manneras to violently agitate the same. Desirably such means are incommunication with the air inlet' 1| and have one or more lateraloutlets abovethelevel'ofl the powder in the tank.y f

In a preferred embodiment herein shcw'n,;a vertical air tube 13 isprovided,` extending the major part of the height of saidl tank andthread'- ed at its lower end 14 into vthe upper` end 'of boreicfinletplugll. 'Y

The upper end of tube13 hasaf-ttingfl/E- threaded thereon, eachlaterally fextefnding'arrn 16 of which has threaded therein =asubstantially L-shaped air agitator tube-11, thedownwardly turnedportion 13 respectively of eachof which is provided with a nozzlev 19and isy curved inwardy, said portions'l each being inclined from thevertical. such that Veach nozzle19, which has an aperture thereinoapproximately .067 inch, will direct a" jet of air at a downward angleof about 38 tod() degrees across radii of the tank toward the'opposingsurface of the wall thereof and as; the nozzles n 'i9 are'displacedfromthe centerof the tank,`the

Preferably the' curvature of portions 18v` isY jet of air will strikethe wall atsuch an angle as l ranged to whirl the air in acounterclockwise direction, the mixing action being the same.

The spray tank 24 is provided with a sight glass 3| identical to sightglass 48 in the dehydrator tank S, comprising as it does a bushing 82threaded into an opening in the wall of the spray tank 24 `and having aglass disc 83 affixed as by cementingorgluing on'iafseat 84`atithe inner'end of the bushing. 'Y f- /In order that the interior of the spray tankypart of thespray tank is desirably equipped with an electric lamp S5threaded into a socket 36 af- 'iixed in anopening inthe tank 24. Thelamp 85 is constantly illuminated While the device is operating so thatthe v'powder cloud set up in the spray tank 24 may be inspected to checkon lthe operation of the machine.

v To bviate'the obscuration of the sight 8| from the heavy deposit ofpowder thereon incurred in operation Yof the machine, cleaning means areprovided vfor .the-sight.y lSuch means comprises a rod- 89extending'through a bearing 9| threaded in an opening in the v wall ofspray tank 24 below sight 8| thereof. The portion of rod'89 extendinginside the tank is upwardly bent as at 92 with a flatangle end 93-parallel to the face of sight glass 83. screws and rubs over glass 83when rod` 89 is rotated byaknob 95 affixed to the outer exposed end ofrod 89. A pin 96 transversely` through an opening in rod 89 adjacent theinner end of bear--Y ing 9| coacts with va pair of pins 91 ailixed onthe inner end of the bearing and extending laterally inward therefromvtolimit the rotation of rod 89.

Mounted at the top'of the spray tank 24 is an outlet head |99 comprisinga valve stem bearing I avalve top I I2 l and a valve base I I3retainedtogether by'screws I I9 'extending therethrough into a threaded openingl041m the top of the sprayI tank. A stop plate |54 is also providedsecured :to valve stem bearing III by screw'l ID, a tight seal beingmaintained between the stop plate IEA and the valve stern bearing I bygasket |58. Base |3 has an internally threaded stemIId extendingslightly into the interior of spray; tank 24 and an inlet sleeve I l5 isthreaded intostem H4. Sleeve I5 has a bore I I6 leading into stern I 4and a plurality Aof openings I Il are providedextending through sleevei5 into-bore Hethereof. :The valve stem bearing II has a bore-H9extending verticallyv therethrough, countersunk at both ends thereof asat |2| and |22, and a transverse bore |29 lextends therethrough andintersects said vertical bore H9. An annular recess |25 is providedinvalve stem bearing III coaxial with the .narrow end of bore |23 and oflarger diameter than such end. Atapered feed valve sternfIEi nts intothe correspondingly tapered bore, y|23 and has a reduced threaded end|21 whichextends beyond recess I 2li. YA laterally eX- tending1 pin |29is aidxed lin the `vshoulder |29 formed by reduced end |21 and fits intoa correspending opening |32 in a valve stem washer |3| positioned inrecess |25 andretained therein by a nut |33 threaded on end |21, the nutserving to retain the valve stem I 23 in bore |23.

Yalvestem I 26 has -a bore |35 extending transversely therethrough and atransverse Abore |36 at. righty angles to bore |35. Valvebearing isvalsoprovided vwith a transverse bore 31 extending into bore |23 thereof andhaving a socket |38.in which is threaded the nipple'end of a cross pipe|39 carrying a T-coupling |49 `at its A lbrush 94 is secured to angleend 93 by' y-lueinthe spray position .withngbore t3-5 :thereof ...bore.|36 n`willchefaligned with .the upper portion f bOI'e' H .9 .thuscutting-off;communication with the ,Spray -ftank l'2 4. andfperrrl'ltting vairrtofheloloufr'i s ltlzlrough-the -outlet :head:.llilinr-tl'le maurleriherematter described.

-.:elve,top. l |12 thas .af-.here 151. therethrougheountersunk.ontits-ioottomestati!581 and in imitapositionftothe.eountersunkportion Ritter-:form .farmixleg .chamberto-.facltatemixing of :ima-nd postuler.' -A booster fitting .ltwhichzis'wprefeb-'ably..cast:irom 'bronze...has al vertical `here .L52 therethrough,:threaded ;at .flower .endV oinzza nipple .r5.9 Y.in -turn i. threaded.into the nhere '1.1.51 igf..the.ualve :top -z 2, .Fittngl 6|. also has.avhore talextendihg at.;i=tn.angllofrv approximately '20 .degreesfinto.bore .tzznearsthe V.upper :endoffathe ittinggandhas a-threadedlower endHill to which ,is .connected .1a. bushing .I 6.5 holding a tube 1.65,one .end il 61 '.of which extends :through 'bushing A|64 .zand'hore `|63.into bore .|62 and .thetother end ..|10 of-whchis connected'to nipple11.68 of .boosterneedle :value |69 fconneeted It@ .tlle'zupller .end :of:Tr-coupling |43.

.Threaded on the upper-'end of 1the'Iloooster.aitting |6| is.dvidinghead which, as shown in 7, .illustratively has :two'topenings|12 therein, .ineaeh .of which I.is .desirably threaded .a double powderfeed .113., provided with shuteoi hand .cocks |14 for :each yoi' l theoutlet lfcoumille'fs |15 thereof, to turn .on tand off the air'fandpow.-.der stream. In thefembodiment of'Fig.' ilvorlly .one .outlet Aeoupling.-i-s utilized; Ithe?aothers rhe- .ing shut 01T yhy handaeocks |14.

. A ySpray tube 23 desirably :extend-ing horizon tally betweenhrackets-l'iarld directly oi/export, if desired, .under the usualhorizontalwsllirface to be sprayedfiis .fedfthrough distributorpipe a-221 from the respectieve fopen outlet :coupling -rl El 5.. Distributor.pipe 22 -leads yirito a Y iitti-njg |116 .having v an air relief'yalveITI which is conneeted .to the `feeder inlet .end of .Spray tube .23.

'Ina preferred embodiment of the '.spray-,:tlrbe 23 shown in Figs. V1and 9, theLlength 'thereof iis y.corrugated,fas shown, "along theeffeetive'iwidth .Qfitheaeurfacefte 'loei.c '.\',a`.ted. "Theseeorrugatorls are-.desirablytuniform y'in length Landheight.' Theacorrugations are -preferably -of l'such height that the crests thereofin 'thewal1-of the-h'ore'vare 4 substantiallyaligned'iwith theftreuefhs`thereof at' fthe 'zdian'ie,tr-icallyA opposite #walljiportionf'fas ashown'fby Adotiand A'dashli'nesih f9,. Y y

`The spraytube- 23 has r sprayapertures IITI'S that are "equidistantandAat' `One'side .ofthetub'e 23 :and fir-lv linear alignment. 'lili-ey.areillrefei` ably not .at the verytrough o,f"=theeorrugations, butveach aperture ls'spaeed ,slightlyibehlrrdisaid trough, Ythat is;'somewhatllarther friolrl .the tube ".outletzthan is' the bottom .of.lzhejtroueh., 'T'Ihe .epray- -aper'mres are preerahlyinelined so '.thatthey slope downwardirom the boreolthe :spray "tube 'iand ioutward in'direction .opposed .to ofthe 'air'.iiow therethrough.

ilustres. .begifnnmget the 'reed fendl :ofithe -zthefleng-.th-;thereoff:due1.-to .its escape `from them)- ;ertureftherein, :therewill :be a .tendencyfaforn the *powder*-` to'; rush fpast fthe .aperturefclosest to the feed :end .In Sorcier... that .the output. .ofzgpowderfrom each aperture beeubstantially.thelsame .the spray 1 aperturesfarerdeeirably `erarialiated in eize', .heine .largerfat lthe. feed :orinlet :end .oiffthe eurer .'tzube-.iLIluStlatiYeIy ...0&5 inch :indiameter and/.decreasihgwto .approximately .-03 11i-heh. 'in faepray:tube having '1a spraying .ieriethfelfv =60 .ltuloe, there will beten..,|.16.5ff.ii1ch apertlires,` .,hirteen 503.6'. inchia-perturesfe deig-ht. ,0.3.1 `inchallertures. Thus asitheapowder rueheshy :thelarger-dahertures vat. the feed erid of :the spray-tube substanfitiallythefsameuuantity willeseope therefrom-vas :from the. smallerapertures at :the opposite .end of, the .spray tube.-

Each of the apertures |=|=9..i s preferably in iadvanee vofthertroughss-.and is Aflooredfirlto the tube afterthefsamehas beencorrugated. Pref.- eral-bly the exis .of...t he .tube is. inclined.slightly :to an' .ane-le of about' 3/ deereesiorsuch drilling-.sothaiathe .vertically i rected drills will bore theapertureatedownwardainelination. l Y v .erder.toprevent backingupeoipowder and `air inthe spraytube which-might elog'the same.a-breatherl provided' the operation .of-which will be. hereinafterdesc'iribed in detailwglvhe .breather .comprises-.atop cap 10|.threadednfon the open end of a'pipe |8'2 connected totheend of .the.spray k.tube .2.3, .An Aouter shell-.|83A is .threaded Einto cap |B.|Yso as to hang vdowmilfard therefrom. -.A .loottomrap 48A having a tube.13,5 threaded into eurngoeriirigV |86. therein, is 'threaded von.theLbottorn .end .orsheill L83.. vThe 'tubey liS lof .suchleneth as `toextend url-.Ward to. nearly' 'the opening 1|.6.0.in.to p cap '|.8..|.andis plugged at 'its ,upper .end asat .|81 .andprov'ided with anapervture .las .through the wallthereof extendinglirlto .the `hereofthetube i185.

In order to energize the solenoidfyalye il .and the lamp ,85 during.operation .of the ,devicathey are .connected :in Iparallel withl main`2:05 which .has awiteh '20.6 in .circuit therewith. ,A 4,m,elfeufryswitch 2011s .also provided .under .control .ofthe 'more.or..lessremoteemeehanism whenlthelslr'ayf 1 amid .ualve .6lwill @be energizedLand .open .andthe ,lamp v'vlll'loeilluminated.v '.Compressed airfwill.passiromL-the source of .pneumatic .pressure v (not shown) tolnletgflttingl which .dschargeeirlto ,aiulter .2 1 :Whereltheair .willbe oleanedahd their passy through `pipe Yfit! .and-presume regolatori]normally .set at .50` pounds .as indicated eri-gauge .3.2iA .Eromthepressureregulator theair will .pass thm-ugh -cross pipe 33. and shuteo...cock 3.4 through meshscreene which-prevents any" hriis orioreignmatter.. p.assirlg therethrough,.ihtothe .bottom ofthe .dehydrator tank30- The air after being dried in its passage through the silica gel inthe dehydrator tank will `pass through mesh screen 56 to remove anyparticles therein and then pass through pipe 59 and the open solenoidvalve 6|, through cross conduit 62 andpipe 63 to pressure reducingvalvev G4 where thev pressure is set to from 2 to 5 pounds as'indicatedon gauge 65. The air then passes through pipe 66, open needle valve 6lto the spray tank by way of the bore 69 of Vair inlet plug 1| 'andthence through air tube 13 and out of apertures 'I9 of the agitatortubesl 11, thus delivering two currents of air 'which will be whirled inaclockwise direction at a downward angle, as shown, of about 36 to 40degrees. 'f

vIn ordinary spraying, as in thev graphic .-art industry for example,the needle valve 61 'is kept open at all times, but in some applicationswhere it is desired to increase the pressure ofthe air entering thespray tank 24 Without increasing its volume the size of the orifice inthe needle valve 61 can be slightly reduced. f

vAs a slight pressure, approximately 2 -tov `5 pounds will be built upin 'tank 24; when valve handle '|53 is in spray positionL Withbore ||9aligned with bore |35, some of the powder from the cloud formed by thewhirling air currents set up in the tank 24 through pipes 78 will beforced through'the outlet head |09. f v

In order to increase the intensity and 'quantity of the air and powderstream from'outlet head |09, needle valve |69 is manually opened topermit'ajet of air under the initial relativelyhigh pressure ofapproximately 50 pounds to be forced through tube |66` into bore |63 ofbooster fitting |6| and thence into bore |62. The path of the air isfrom inlet tting U, air lter 2l, pipe 29, pressure regulator 3|, pipe33, shut-Dif cock 34, dehydrator tank 30, pipe 59, solenoid valve 6|,pipes 62,' 63 and |5I, needle valve |59 and into tube |66.

The'movement of the air will exertran effective suction on tank 24 todraw additional particles of powder therefrom through bore 5' andaperture ||1 of sleeve ||5. It is of course apparent that the greaterthe air pressure or velocity of the air through bore |63 of the boostertting the greater will be the amount and intensity of the powder streampropelled through the outlet couplings |15 and the distributor tube 22to the spray tube 23 wherefrom it is sprayed on the surface beingtreated.

It is to be noted that in passing through the spray tube 23, theobstructions imposed by the corrugations therein will intercept some ofthe powder entrained with the air forced through the feed end of thetube 23 while some will be blown through the apertures |19 for thespraying action desired. The location and size of the spray y apertureshereinbefore set forth brings about an effective and uniform spraytherethrough, both through those near the inlet of the spray tube andthose remote from the inlet. It is to be further noted also that werethe obstructions imposed by the corrugations omitted, the spray would be`far from uniform, as some holes would deliver with the diametricallyopposite troughsy of'such bore, it has been found 'that the resistance'.im-

posed in advance of each spray aperture is exactly right for bringingabout the uniformity of distribution. The disposition of the sprayaperture |19 slightly beyond the bottom of thel trough and in thedirection set forth, assures axuniform ysymmetrical spray Where thelocation'of such aperture elsewhere or at a different angle would leadto a spray deflected either to the right or to the left from that shownand thus render the distribution less uniform.

It willbe understood that while in general the spray apertures are atthe forward side of the sprayA tube, the corrugations of whichA lie in ayhorizontal plane, as best shown in Figs. l and 9,

the plane of the corrugation mayfor certain applications be tilteddownward or; rin some cases, it may be tilted upward to the desiredangle yfor spraying the underface of a sheet or plate passed thereabove.The length of the spray tube of the present invention may be extendedobliquely or even vertically for certain special applications as,for'instance, the coating of a wall or a silo, and the distribution ofpowder'is found to be thoroughly uniform in any of `such applications.

It will also be understood that two-"or more of the spray'tubes may bearranged in parallel and in slightly cascaded relation for greatprecision of powder distribution. ln such case the outlet head of thedevice would be equipped with a sucient number of outlet couplings fordis'- tributor tubes to supply all of such spray tubes.

When the air and entrained powder that is not discharged through thespray apertures |75 reaches the end of the spray tube they will enterthe outer shell |83 of the vertical breather device through tube |82. Asthe air' pressure during its passage through the distributor pipe 22 andspray tube 23 has decreased from approximately 2 to 5 pounds in the tank24 to but a negligible amount when it enters shell |83, the powderparticles will drop to thebottorn thereof which is sealed by bottom cap*|86 while the air will escape through lateral'aperture |853 in tube andout of opening iSd-'in bottom cap |86. As aperture |88 is nearvthe topof the breather |80 normally no powder will escape therethrough.However, when' the powder level in the shell rises up to aperturel'a'mist of powder will be ejected from opening it in the vbottom of thebreather instead or" clean air.

This will indicate that it iis time to empty the shell which is done byunscrewing the shell from its top cap. The powder thus emptied may besalvaged for re-use. f

Throughout the operation of then-spray apparatus the operator mayinspect the efficiency vof the powder cloud and 'determine the level ofpowder in the spray tank through the sight glass to assure bestoperation.`

When no .further spraying is required, it is desirable to clear thespray tube and distributor tube of powder remaining therein as exposureof the latterto the atmosphere for any length of time may result inclogging and contamination, especially if the powder be ofhygroscopiccharacter. To this end, valve handle |53 inthe outlet head is moved fromspray position to blowout position. Valve stern |26 lwill thus be turnedin its bore |23 so that communication to the spray tank 24 will besealed land bore |35 of stem |26 Vwill be aligned with bore |37 of valvefitting to providel a passage for the compressed air which is under arelatively high pressure of 50 pounds from the compressor (not nosed;

andere showni-iwhich f path `ofithefa'4 Liprpe 29 through-pressureregular@ it 'and crosse-pipette intoiidehy'dr'atorl' tankwSU omtheloutletjend ofi'saidi tankthroughi ipe-5592 vailve cross pipe 62, pipes69, and |39, throughffbores |31; -ISf-and I 3 6 intobore |62y otb'oosten1fltting IS'I their 'tnrougl'r'distributoripipe.1izz-f'andrspray tube` "3. Thus the distributor 'fpip landespray "tuba-#willbehlown 'clearJ l'of' powde "forcing i such throughsightglass-48pv f i:When the; gel.- ;isibl-ue',xthes'air passing' here-1 throughctoward theSupper: end.' of: theadehydrator tank.' .is .-dryt. 'and'.r the?vfdehyldrator: isY functioning prop'erlyi .rWh'en:I the.gel-iisfapinfl'ri.y or salmoni-:in color'glit is; saturated to-aboutflOpen cent,.rel ative .humidity and... should: be; replaced 4:xvii-hice,refill fof" activated iflblue) Egel. y.f;Remo'val.{or}the bushing 45.allows theasaturated gel-.tosdrain from the dehydrator tank. Whentheibushingf. 45.-'has beenreplaced with shuteo-.i'c'ocls:431.closed,.the sight?- .glas's 43,.' is :removed fori refilling the; deehydrator-" f" f 1 Y w In. order to replenis-he` .thea-.supply`poi/voler.

yin..fthe-spray `tank'. 24;, ia :powder supply tank'. v.99

isadesirably. mountedI adjacentato andi at.V ahigher levelth'an spray.tank.124,.:byumeansifoflazbracket lillnconnected to fthe. bottomifo the.lpowderctahk 99fby= rscrew 1-|D2an`d= to theisde..wallotztliesprayvtank 1. :by screws ll .'Ifh'ez, top f of theip'owder supply tank Y(:lo'sed'fb'y 'a :cover-'1: plate'. :|081 fremovably' threadedf'threon:at A101'.- Communie tion .'-f'islsestablished between hey powderrsupplytank ..99f-5andrthe. vspray,'talnkii1241' by meansI pi i a nipple: :10-5 'Lhavng A.-a=1valve' |ll|fitherein.- :To ...re-v plenish. the.`spray tank;theopowdensupply .valve |06;t .isrnpe'ned.-,allowing.i ,thec'ompressed; aimirom the fsprlaaf.-` .tank `l249.130: pass..linto",fsupply:I tank 2:99 which had, :prevouslyxheerr lled. with".ypowder; Inasmu'chrzas tank x99. .hasn-no: outlehrexcept'. that providedby valverlll 6 'air pressure :will ib -built up therein. .f f i.; .v y

In order to,break th'e/ crcuititoathe solenoid valve 6| thereby causingthe latter to close and shut off the air supply'tof *thefspray tank 24,a switch button 208-.is provided-inseries with said solenoid valve 6|.With therbuttonf depressed and the valve deenergized andclosed the airin the spray tank 24 will' thereupon escape through open outlet head=||l9- causing thelprese suregin tank 24 to fall. 1-

he Vgreater.pneumatic lpres's'ure now "e sting insupply tank 99 willleffect expulsion 'o'fpbwder therefrom through' V'open' Vvalve "i 06into' @spray tank 24'. By alternately press-ing and rel ing the button"208 'the' process of' transferring p der fr' 'thesupply tankto'th'espray tanks ntf 'eduntil the llatterv is Jhal'fynlledx th o'u'ghsi'e'ht'glass 8|. ValveL-IUB is th procedure `eneroies. the operatoreplen'ishthe 'spray tank wit' powder Jfrbrn'the supply tank 99 evenwhile the spray is operating. However in cases where it is desired tofeed large quantities of powder the above method of supplying the spraytank 24 would require too much manual attention.

Toremedy-this -i'orJ industrial dusting operations', :an automatic timer209 is provided shown in clashes in Fig. 1. This timer, theconstruction'ofwhich is-vconventional and which per se forms nopart-lofthisl invention, y replaces switch 208 in thecircuit'and hence is inserieswith the soler'ioidv Valve 6|; The'electrio'timer 209'is set,auton'laticallyto r open?` andi close the solenoid valve 'approximately1Ar'second.out of every 30 secondsto control thel feeding ofpowder in'tothe spray tank 24 as above described, when normally closed button 208iis pressed toA open thecircuit to valvel I I In the use of theautomaticltimer 2GB, valve |96isi-.openedsufficiently*toi admit powderinto the spray tank L24 each 30 seconds, at substantially' the rateofiusefthereof., thereby to maintain.l a `substantial.constantlevel ofpowder in thejspraytank.'a.... l L

. In .the embodimentfof:.thepbreatherdevice la shown :in Fig.. 12.a top.cap |8|. isprovided, threaded 'onthe open end of. pipe ,|82 connectedto the `,end -of the spray tube A23;V A cylindrical container:I|`83-.,is; threaded into .cap I1.' soas` to hang downwardly therefrom,and an` air relief valve 2fi0is positioned on. ,capA 18| incomrnunicaEtion .with the interior-of; container |83'.

, Thus when.:the Adeviceisl in; use, the air and entrained powderthatisnotdscharged through theepray apertures |1'|,9,wher1; they` reachrtheend et' the spray-tube 23, will enter the; container seit of theyerticalbreather. vdei/ice |80 through tube: 182;., As, the. airpressure during its passage through the distributor pipev 22 `,and spraytube 23- hasldecreasedas hasibeen heretofore; described,

the-'powderywllqfall tothe sealed; bottom of the container |83.' andremain therein while the air willrescape.throughlair relief valveZilli). Asthe I :'In-y Fig-10,thefdevicerhereinsrshownesapplied toahust;ichaxnher.;4 |9|fonsprayingnmaterial `in motion. In,thisiapplication :the four outlet 4cou-l Y plingsf-.lflff are:utilized...eachp'connected,respec-v tively bya'riistributontubei 92 toan;.ejectorg pipe |83 igslidably: mounted; in; :a bearing. |oushingv..4|94 afxedzto: .the` side.; .wall l of .the dust;- lchamber |91?. The.ejector :pipesnl Maarre. mounted vvin pairs:ofi'eachisidewallf|.95rsofasfto sprayi powder `over the-webfaot:material fllxwhich:moves 'longitudinallyrthrough :the ichamber 19| Thev.slidable pipes may be adjusted laterally to accommodatefordifferentwililthslofweb@v f im? .Figa-'#11 'therdeviceiisgishown asiapplied tov a,:new:hirie v 91 tor linanufacturing. extrudedtubin'gillstratively o'f rubber'. this` machine itse'lif is:vconventi'onal .andiorms l per sev no part of thisinventifin,A it `willln'ot'be describedin detail. One' of thdoutlet -couplings i 'lfisvl*connected by -distributor tube |98f'ft'olan ejector 'pipe |99,theI"nozaleendv Zul-fof `Vwhiclr-extend s-#intothe bore oftheHeXtrudedf-tubing as -it' emerges `,f-rovrnlthe Inachine;A lif'a'iiddust'sftheinterior yofl such tube, therebypreventing the 'wallsv`of``the same from sticking together if they should contact each other.

It is of course to be understood that the applications of the deviceherein shown are merely illustrative of the many uses to which it can beput and are not intended to limit such uses in any way.

As many changes could be made in the above construction, and manyapparently widely different embodiments' of this invention could be madewithout departing from the scope of the claims, it is intended that allmatter contained in the above description or shown in the accompanyingdrawings shall be interpreted as illustrative and not in a limitingsense.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent of the United States is:

1. A dry powder spray equipment comprising a powder spray tank having anoutlet and an-` inlet, means for delivering compressed air into saidinlet, one or more fixed nozzles in said tank connected to said inletand each positioned to direct a jet of air across radii of said tank anddownward into the powder in said tank at an angle of less than 90degrees, to whirl said air in an oblique path thereby to stir up a cloudof powder in said tank and means associated with said outlet forcreating a suction in said tank whereby powder may be entrained fromsuch cloud for delivery to the surface to be sprayed.

2. A dry powder spray equipment comprising a tank for dry powder, havingan outlet at the top thereof, an upstanding tube in said tank risingthrough such powder and connected at its lower end to a source ofpneumatic pressure, fixed air agitator tubes aiiixed to the top of saidfirst named tube and extending substantially laterally therefrom, eachof said air agitator tubes having a curved, downwardly extending portionhaving a nozzle at the end thereof, each of said downwardly extendingportions being tilted from the vertical so that said nozzles may directjets of air across radii of said tank downward toward the bottom of thelatter at an angle of less than 90 degrees to whirl said air in anoblique path, thereby to stir up a cloud of powder in said tank andmeans associated with said outlet for creating a suction in said tankwhereby powder may be entrained from such cloud for delivery to thesurface to be sprayed.

3. Powder spraying apparatus comprising a tank for powder, meansconnecting said tank to a source of compressed air, means in said tankactuated by said compressed air for stirring up a cloud of powder in theupper part of said tank, an outlet head on said tank and normally incommunication therewith, means connecting such source of compressed airdirectly to said outlet head, and a feed valve in said outlet headshutting oif communication from the tank therebelow and directing theair blast through said outlet head.

4. A dry powder spray equipment comprising a powder spray tank having anoutlet head at the top thereof and an air inlet at the bottom thereof, atube connected to said air inlet and extending upwardly into said tank,means for delivering compressed air through said tube, means to dry suchcompressed air before delivery to said tube, air agitator tubes affixedto the top of said rst named tube and extending laterally therefrom,each of said air` agitator tubes having a curved, downwardly extendingportion having a nozzle at the end thereof, through which the v12compressed air delivered through said air agitator tubes may be expelledthereby stirring upa cloud'of powder in the tank, and means associatedwith the outlet head for entraining powder from such cloud for deliveryto the surface to be sprayed.

5. Powder spraying apparatus of the character described comprising atank for dry powder having an inlet thereto at the lower end thereof,means connecting a source of compressed air to saidinlet, means to drysuch compressed air before passage thereof through said inlet, anoutlethead at the top of said tank and normally in communicationtherewith, a` tube extending upwardly in said tank from the lower endthereof and connected to said inlet, air agitator tubes affixed to thetop of said last named tube and extending laterally therefrom, each ofsaid agitator tubes having a, nozzle, the compressed air deliveredthrough said nozzles thereby generating a cloud of powder in said tankand building up pressure therein to force powder from such cloud in saidtank through said outlet, means connecting such source of compressed airdirectly to said outlet head and normally not in communicationtherewith, and a valve in said outlet head to close off communicationfrom said tank and provide communication from saidrlast named meansthereto.

6. Powder spraying apparatus comprising a tank for powder, meansconnecting said tank to a source of compressed air, means in said tankactuated by such compressed air for stirring up a cloud of powder in theupper part of said tank, an outlet head on said tank and normally incommunication therewith, means connecting said source of compressed airdirectly to said outlet head, a feed valve in said outlet head shuttingoif communication from the tank therebelow and directing the air blastthrough said outlet head. a lamp in said tank near said outlet head, asight glass mounted on said tank through which the illuminated interiorof the tank may be viewed and means to clean the inner face of saidsight glass, `said means comprising a rod extending through an openingin said tank and `iournalled therein, said rod havinga brush aixed toits inner end in juxtaposition to the inner face of said sight glasswhereby when the extending end of said rod is rotated, said brush willsweep over said glass to clean the latter.

CHARLES` WILLIAM BRITCHER.

REFERENCES CITED The following references are of record in the ille ofthis-patent:

UNITED STATES PATENTS Britcher May 15, 1945

